Lighting fixture with air diffuser



March 1965 E. P. BUCEK ETAL LIGHTING FIXTURE WITH AIR DIFFUSER 2Sheets-Sheet 2 Filed Jan. 18, 1961 FIG 7 F158 INVENTORS Edward P BucekWa/fer Sfier d5 [/ZZzMw Hm Ahys.

United States Patent l 3,172,350 LIGHTING FIXTURE WITH AIR DIFFUSEREdward P. Bucelr, Lyons, and Walter Stier, Chicago, 12]., assignors, bymesne assignments, to Curtis-Electra Lighting, Inc., Chicago, ill.

' Filed Jan. 18,1961, Ser. No. 83,504

3 Claims. (Cl. 9840) This invention relates in general to light fixturesand more particularly to fluorescent light fixtures which are adapted toprovide a port for the conduction of either ventilating or exhaust air.

For the past several years a practice has developed of connecting an airduct to a light mture and passing air through the fixture into a roomtherebeneath. This has been especially popular with fluorescent fixtureswhich may line a good portion of the ceiling of a room in manycommercial and industrial establishments. The ducts are arrangedadjacent the room ceiling so that certain spaced apart ones of thefixtures are fed cool or warm air depending on the season and otherfixtures may serve to provide vents for the exhaust air in the room. Theduct work and other apparatus such as the plenum chamber through whichthe air is fed are usually concealed by a false ceiling which generallycomprises an acoustic material and which may abut or slightly overlapthe edges of the fixture to provide a flushror smooth appearance betweenthe respective edges.

The practice of passing air of different temperatures adjacent thefluorescent tubes or lamps creates undesirable effects. Thus therespective .tu-bes, if operated in an environment of differenttemperatures, have different light efficiencies and different lifeperiods thereby creating very unequal lighting and maintenanceconditions for the various fixtures, and in various parts of the room,as some fixtures may alternately pass warm or cold air, others eithercold or warm and still others no air. It may also be mentioned that coldair passing adjacent the lamps may cause the color of the associatedlamps to.vary from the colorof the other lamps thereby creating adisturbing visual effect.

In addition, since the ducts which feed or exhaust the air are broughtinto the fixture through the top and as a plenum chamber is generallyprovided intermediate the fixture and feed duct, a substantial spacingmust be pro vided between the acoustic or camouflage ceiling and theprimary ceiling from which the fixtures and ducts are supported. Thisresults in a great deal of lost space, but solutions to this problem donot permit widening the openings in the camouflage or acoustic ceiling,which openings are of a predetermined dimension. ;Further, the door orclosure structure by which the lamps are enclosed, but which permitsaccess thereto must be arrangedso as to provide no interference with theapparatus through which the air is carried and furthermust be level orflush with the bottom of the fixture to preserve appearances.

Another-problemthat should bementioned in conjunction with such fixtures'is that the installation and maintenance thereof has resultedin-jurisdictional problems between various unions as to their areas ofresponsibility. Thus, members of electricalunionsmay, for example, berequiredto return after their original work is completed anddismautleaportionof the'fixtures, before a member of another union can repair orinstall the air conduit or duct work related to'the fixture.

It is therefore an object of the present invention to provide animproved fluorescent light fixture which may also serve toprovide an airconduit.

-It is a further object of this invention to provide a light fixturewhich permits either exhaust or ventilating 3,172,356 Patented Mar. 9,1965 air to be extended therethrough without creating unnecessaryinterference with the lamp operation in'terrns of either the lampefliciency or maintenance.

It is another object of this invention to provide members for afluorescent fixture which can interchangeably be utilized to enable thefixture to serve as a source of ventilating air or not as required andwhich ma also serve to rigidize the fixture during shipment.

It is a further object of this invention to provide economical closuremeans for a fluorescent light fixture which can be interchangeablyrelated to the fixtures'oas to provide desired access. i

It is yet another object to provide a closure means for a combinationlight and ventilating fixture which may be disposed flush With fixturesurface and which will present no interference to the installation ofair conduits disposed along the fixture side.

Other objects together with the various features of this invention willbecome apparent on examination of the following specification, claimsand drawings.

FIG. 1 is a broken bottom elevational view of a fixture incorporatingthe principles of the present invention;

FIG. 2 is a sectional view of the fixture shown in FIG. \1 illustratingthe relationship of the air conduits to the lamps;

FIGS. 3 and 4 are respective enlarged sectional views illustrating theport and door closure structure;

FIGS. 5 and 6 illustrate the door hinge and latch arrangementrespectively; i V

FIG. 7 illustrates a portion of the port control channel, and

FIG. 8 is a sectional view of the channel taken through the line 8-8 inFIG. 7.

In FIG. 1 a fluorescent fixture or trofl er 10, commonly called adiffuser troifer, as seen for examplefrom floor level, is illustrated inpart. The trofier10 comprises a door or closure portion 12 through whichaccess is had to the fluorescent lamps 18 and an outrigger or flangeportion 30 adjacent each elongate side of the closure .12. The trofferas is well known comprises inclined side walls 20 and top wall 19 each,havingproper reflective properties for directing light from lamps 18into the room beneath the fixture. The socket connections for the lamps18 areomitted.

The door 12 comprises sections :14 on opposite short sides of thefixture and the elongate sections 16'for the opposite long sides ofthefixture 10. The flanges :30 each have an elongate rectangular opening orport 28 therein as best seen in FIG. 2, which may eitherbe left open orhave the legs 32 or-34engaged therein.

The flange 30 is simply a continuationofthe wall .29, which is providedwith a horizontal wall 56 that joins the vertical wall 3;1 beforecompleting the juncture to -3! h op inao r l fl n 3 i m by bending backa cut-out portion from flange 30 toforrn the Wall 39. Flange 30isprovided with a 45 .ang le ice bend 54-, whose only function is toserve as an abutment joint for acoustical tile in the false orcamouflage ceiling, which is laid in ilu-sh with theplane of flange 30.The bend'54 may, of course, be fashioned in any nurnber of manners ordiscarded, depending upon the'type 1of ceiling and the type of joint tobe made with the camoufiage ceiling. From-FIG.'2 it will be seen thatthe troffer 19 is supported from the primary ceiling by meansof thesubstantially U-shaped strap 59 and the toggle bolts 55 engaging the topwall 50 of the fixture .10.

The strapSli and toggle bolts 55 are of welljknown type and the fixture.19 is hung thereon betweenone or more air conduits or diffusers, if thediffusers are to be used with the fixture. Neither need then bedisconnected to permit work to be done on the other. This removes onearea in which unnecessary expense or jurisdictional problems arise dueto the necessity of permitting, for example, an electrical worker todismantle the fixture for permitting either final connection oradjustment of the air flow damper to be performed by a worker in anotherunion. The vertical legs of the strap are omitted as these simplyperform well known functions in connection with supporting portions ofthe acoustic ceiling and/or air conduits.

The ballast and connections (not shown) for the lamps 18 may be locatedbetween walls 22 and 60. The retaining wall 22 supports the reflectivewall 19 and has flanges which retain the self-tapping screws 15. Thesescrews 15 fasten the retaining wall and may, though not necessarily,protrude through the side walls 20 to separate the air conduit 11 fromthe fixture 10. An insulating space between fixture and the air conduit11 extending from the plenum chamber 17 is provided by the contour ofthe air conduit when installed in the slot.

The conduit 11 and chamber 17 are each provided with a top flange at 65and 66 respectively which rest on the wall 60 of the troffer and each ofside walls 61 and 62 also have a bottom horizontal flange which may reston horizontal leg of the channel 33 and the horizontal leg 56 of theside wall 20 respectively.

If the diifuser troffer 10 is to provide ventilating air, the air fromthe plenum chamber 17 is directed down through the conduit v11 formedbetween the walls 61 and 62 and through port 28. In some cases, as forexample when a pressurized ventilating air supply is provided, the openportion of port 28 is defined by the inclined leg 34. Normally, however,the port 28 is left completely open if supplying ventilating air. Theleg 34 also may be associated with the port 28 when the port is to beused for an air exhaust. In this case the leg 34 serves to disguise theport and prevent the intake of impurities. Alternatively, air may beevacuated from the room when the leg 34 is removed from port 28. Ineither event, warm air can simply rise through the opening 28 intoeither the space between the ceilings or an exhaust duct. Due to thefact that Underwriters Laboratory has dictated that no passage beprovided through the fixture to the space between ceilings in order tominimize the danger of spreading fire, the trotfer side which is not tobe used for passing air has its port 28 closed, as shown in FIG. 4. Theleg 32 is then provided in port 28 to completely close the port 28 inflange 30. The legs 32 and 34 are each opposite legs of a channel memberhaving a substantially U-shaped cross-section with the leg of the Udesignated 32 bent inward.

Referring now to the channel section 33 as seen in FIGS. 3, 4, 7 and 8by which the opening or port 28 may be controlled to provide an air pathfrom the plenum chamber 17 or to close the port 28, it will be seen thatthe bar of the U is provided with a number of cut-out legs 29 that arebent transverse to the bar. Thus, when the bar of the U-shaped channel33 is placed against wall 39, the cut-out legs 29 are sufliciently longto ensure that the channel 33 is held quite securely when snapped intoposition between the walls 3-1 and 39 to snugly retain the U-shapedmember 33 in position during shipment. In

addition, the screws 35 are provided at several positions.

along the length of channel 33 to ensure that the walls 39 and 31 aremaintained in parallel relationship along their length and that wall 39mates securely with the channel 33. It will be immediately appreciatedthat the channel 33 can by simple rotation of 180 on longitudinal axisenable either leg 32 or leg 34 to be placed in the port 28 so that portin the trofler 10 may be either sealed completely or used forventilation, as explained. As the channel 33 is of very economicalmaterial and construction, it may easily be discarded withoutsubstantial loss to provide either a supply or an exhaust vent through28 if needed.

The door carries the glass 13 and is provided to enclose the lamps 18within the troffer 10. It fits between the vertical side walls 31 and ishingedly connected to the troffer by means of a pair of hinge elementssuch as 40. The hinge elements 40 are spaced along the elongate side 16of the door and each is a simple substantially U-shaped wire having ahorizontal extension on the side legs which permit the hinges to berotatably secured to the door at the mounting elements 46.

Sufficient friction is provided at extensions 45 to inhibit excessiverotational action of the hinges so that the door 12 may be raised withthe hinges protruding therefrom before mounting on the troffer. The bar44 of each U-shaped hinge is then passed through a respective aperture42 in the side wall 20 when the door is installed as shown by the dottedlines in FIG. 4. The aperture 42 has descending legs 43 on each side toform a tongue 47 whereby after the bar 44 passes through the aperture 42and the door 12 is permitted to drop, it carries the bar 44 of binge 40below the recess 42 so that hinge 40 and tongue 47 are engaged as shownin FIG. 5. The door 12 is then hingedly secured to one wall 20 of thetroifer 10. As may be seen in FIGS. 3, 4 and 5, the hinge 40 restsadjacent the wall 56 and therefore provides no interference to the airconduits.

The door may now be latched in its closed position by means of the latch48 on the side of the door opposite hinges 40. The latch 48, as seen inFIG. 6, engages an opening 52 in the wall 56. Latch 48 is normallybiased into a perpendicular position with respect to the door 12 by thespring 49. When the door is closed the latch 48 engages the edge ofopening 52 in Wall 56 and due to the wedge-shaped construction of latch48, the latch pivots back to enter through the opening 52. After theedge of wall 56 disengages from the wedge-shaped portion of latch 48,the spring 49 causes immediate engagement of the lip of latch 48 withthe wall 56. To release the latch thereafter the lever arm 53, whichextends into opening 59 of door 12 and flush with the door 12, isoperated to free the lip of latch 48 from wall 56. This permits the door12 to pivot about the hinges 40 supporting it at the other side as shownin FIG. 4. As may be seen in FIG. 1 suitable latch apertures 52 andtongues 47 are provided on opposite sides of the trofier 10 so that thedoor 16 may be hinged and latched to either side depending on which ismost desirable.

In summary then, it will be appreciated that a number of troffers 10 maybe suspended from a primary ceiling and that certain ones of thetroffers will furnish a port 28 through which fresh or ventilating airis supplied to the room beneath the primary ceiling. Other troflfershave a port 28 which is opened to exhaust air by, for example,discarding channel 33, while still other trotfers which need furnish nosuch function have their ports closed by leg 32 of channel 33. Onefixture 10 may serve to supply ventilating air on one side and exhaustair at the other; supply air from both sides and, if desired, from apressurized plenum; exhaust air at both sides; close one side to eitherexhaust or ventilating air and provide either exhaust or ventilation atthe other side or have both sides closed to air passage. Each trolferwill be suspended by means such as toggle bolts 55 from the strapslocated about the room after the air difiuser conduit has been mounted.The fixtures or troffer when once placed in position on the toggle boltsby a member, for example, of an electrical union, need not thereafter bedisturbed. The door 12 may be hingedly engaged on the tongues 47 byengagement of the hinges 40 therewith either at that time or at somesubsequent time as needed.

Screws 15 give the desired insulating space between the fixture 10 andconduit 11 while the air flow damper (not shown) may be adjusted throughthe flange port without calling for any work by a member of anelectrical union as none of the electrical facilities need be disturbedby this process. The channels 33, if used, are, of course, adjustedprior to the completion of the installation or likewise withoutnecessitating work by members of diiferent unions. Thus, if the port 23is to provide access or air from the plenum chamber 17, the channel 33may be discarded or if desired to be used, leg 34 is brought intoengagement with port 23 as shown at the left of FIG. 2 and the screws 35adjusted to assure the proper fit.

If the port 28 is to be completely closed the channel 33 is arranged sothat the leg 32 overlies the port 28 and prevents air flow therethroughwhile the screws 35 are likewise adjusted in that instance, as shown onthe right of FIG. 2. In either event, the installation of the plenum andconduit, adjustment of the channel 33, or the adjustment of a damper(not shown) in the plenum chamber may be done without requiring thedisturbance of any electrical components and therefore avoidsjurisdictional conflicts or excessive economic burdens in theinstallation or adjustment of such components.

Thus, having described an embodiment of this invention wherein a lighttrofifer may be used with maximum efficiency to conduct or block air andprovide an efficient, economical, non-interfering closure for the lampportion of the trotfer, it must be appreciated that the inventionincorporates concepts of broader scope than those described and thatthese will be more eifectively set forth in the appended claims.

We claim:

1. In a light trofiier assembly including a base and downwardlyextending side walls, said base being attached to a primary ceiling andsaid side walls extending to the level of a false ceiling spaced apartfrom said primary ceiling with the space between the ceilings forming aplenum chamber, the improvement comprising horizontal flanges extendingoutwardly from said false ceiling, the flange extending from at leastone of said side walls having a port through which air may pass to orfrom said chamber, and means for controlling the flow of air throughsaid port comprising a substantially U-shaped channel member including across bar and first and second legs extending from said bar, means forsecuring said channel member in said assembly whereby the channel memberis positioned adjacent said flange in a manner such that either of saidlegs can be disposed to overlie the port defined by said flange, saidfirst leg extending angularly, inwardly,

upwardly from said bar whereby air may pass by said first leg when itoverlies said port, and said second leg extending perpendicular to saidbar in the same direction as said first leg, means spacing said secondleg from said one side wall to form an air passage communicating withsaid chamber when said first leg overlies said port, and said second legbeing dimensioned to substantially block off said port when said channelmember is secured with said second leg overlying said port.

2. A light troifer assembly in accordance with claim 1 wherein the meansspacing said second leg from said one side wall comprises a central legcarried by said channel member and extending outwardly from the bar ofsaid channel member in the same direction as said first and second legs,said central leg being longer than said first and second legs, a supportwall extending upwardly from said flange at a point adjacent said port,the bar of said channel member being adapted to engage said support wallwhen the channel member is secured in said assembly, and wherein saidcentral leg engages said one side wall to space the outer edges of saidfirst and second legs from said one side wall.

3. A light troifer assembly in accordance with claim 1 including an airconduit communicating with the air passages formed by said channelmember, first and second walls connected to said trofler and extendingin spaced apart relationship adjacent said one side wall of saidtrofi'er, the spacing between said first and second walls defining saidair conduit with the lower end of said air conduit defining an openingcommunicating with said air passages, and including spacer meansconnected to said one side wall and engaging a wall of said air conduitto hold said last mentioned wall in spaced apart relationship withrespect to said one side wall to thereby maintain an insulating spacebetween said air conduit and said one side wall.

References Cited in the file of this patent UNITED STATES PATENTS2,625,646 Goebel Ian. 13, 1953 2,960,602 Kurth et a1 Nov. 15, 19602,962,582 Croft Nov. 29, 1960 3,010,378 Geocaris Nov. 28, 1961

1. IN A LIGHT TROFFER ASSEMBLY INCLUDING A BASE AND DOWNWARDLY EXTENDING SIDE WALLS, SAID BASE BEING ATTACHED TO A PRIMARY CEILING AND SAID SIDE WALLS EXTENDING TO THE LEVEL OF A FALSE CEILING SPACED APART FROM SAID PRIMARY CEILING WITH THE SPACE BETWEEN THE CEILINGS FORMING A PLENUM CHAMBER, THE IMPROVEMENT COMPRISING HORIZONTAL FLANGES EXTENDING OUTWARDLY FROM SAID FALSE CEILING, THE FLANGE EXTENDING FROM AT LEAST ONE OF SAID SIDE WALLS HAVING A PORT THROUGH WHICH AIR MAY PASS TO OR FROM SAID CHAMBER, AND MEANS FOR CONTROLLING THE FLOW OF AIR THROUGH SAID PORT COMPRISING A SUBSTANTIALLY U-SHAPED CHANNEL MEMBER INCLUDING A CROSS BAR AND FIRST AND SECOND LEGS EXTENDING FROM SAID BAR, MEANS FOR SECURING SAID CHANNEL MEMBER IN SAID ASSEMBLY WHEREBY THE CHANNEL MEMBER IS POSITIONED ADJACENT SAID FLANGE IN A MANNER SUCH THAT EITHER OF SAID LEGS CAN BE DISPOSED TO OVERLIE THE PORT DEFINED BY SAID FLANGE, SAID FIRST LEG EXTENDING ANGULARLY, INWARDLY, UPWARDLY FROM SAID BAR WHEREBY AIR MAY PASS BY SAID FIRST LEG WHEN IT OVERLIES SAID PORT, AND SAID SECOND LEG EXTENDING PERPENDICULAR TO SAID BAR IN THE SAME DIRECTION AS SAID FIRST LEG, MEANS SPACING SAID SECOND LEG FROM SAID ONE SIDE WALL TO FORM AN AIR PASSAGE COMMUNICATING WITH SAID CHAMBER WHEN SAID FIRST LEG OVERLIES SAID PORT, AND SAID SECOND LEG BEING DIMENSIONED TO SUBSTANTIALLY BLOCK OFF SAID PORT WHEN SAID CHANNEL MEMBER IS SECURED WITH SAID SECOND LEG OVERLYING SAID PORT. 